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UIViewController viewDidLoad vs. viewWillAppear: What is the proper division of labor?
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viewDidLoad is things you have to do once. viewWillAppear gets called every time the view appears. You should do things that you only have to do once in viewDidLoad - like setting your UILabel texts. However, you may want to modify a specific part of the view every time the user gets to ...
How does '20 seconds' work in Scala?
...g on.
First, Scala allows dots and parens to be omitted from many method calls, so 20 seconds is equivalent to 20.seconds()*.
Second, an "implicit conversion" is applied. Since 20 is an Int and Int has no seconds method, the compiler searches for an implicit conversion that takes an Int and retur...
What's the difference between utf8_general_ci and utf8_unicode_ci?
...pecific conventions; not everybody sorts their characters in what we would call 'alphabetical order'.
As far as Latin (ie "European") languages go, there is not much difference between the Unicode sorting and the simplified utf8mb4_general_ci sorting in MySQL, but there are still a few differences:
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How to get element by innerText
...unction getElementsByText(str, tag = 'a') {
return Array.prototype.slice.call(document.getElementsByTagName(tag)).filter(el => el.textContent.trim() === str.trim());
}
Usage
getElementsByText('Text here'); // second parameter is optional tag (default "a")
if you're looking through differen...
Properly close mongoose's connection once you're done
...e a very simple issue yet I can't find an answer; simply put once I make a call to any mongoose function that sends requests to mongodb my nodejs instance never stops and I have to kill it manually with, say, Ctrl+c or Program.exit().
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Using Custom Domains With IIS Express
...itly (either by opening and accessing from webmatrix, or from command line calling iisexpress.exe (from it's installation directory) with the /site parameter.
In general, the steps to allow fully qualified DNS names to be used for local access are
Let's use your example of the DNS name dev.examp...
How to hide output of subprocess in Python 2.7
...t os
import subprocess
FNULL = open(os.devnull, 'w')
retcode = subprocess.call(['echo', 'foo'], stdout=FNULL, stderr=subprocess.STDOUT)
It is effectively the same as running this shell command:
retcode = os.system("echo 'foo' &> /dev/null")
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Computed / calculated / virtual / derived columns in PostgreSQL
... (Not in Postgres 13, yet) .
Related:
Attribute notation for function call gives error
Until then, you can emulate VIRTUAL generated columns with a function using attribute notation (tbl.col) that looks and works much like a virtual generated column. That's a bit of a syntax oddity which ex...
What are “res” and “req” parameters in Express functions?
...ered
request.method, which will be "GET" in this case, hence the app.get() call.
An array of HTTP headers in request.headers, containing items like request.headers.accept, which you can use to determine what kind of browser made the request, what sort of responses it can handle, whether or not it's ...
ASP.NET MVC 3 - Partial vs Display Template vs Editor Template
...that you can mix and match. For example you could have a partial view that calls the EditorFor helper. It really depends on what your application is and how to factor it to encourage maximum code reuse while avoiding repetition.
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